Use of light emitting diodes, also known as LEDs, in light fixtures have become increasingly popular. LED lighting is more energy efficient and has a longer expected mean time before failure than both incandescent and fluorescent lamp systems. Additionally, LED lighting does not have the warm-up time characteristic of fluorescent lighting.
On initial introduction to the market, prices of LED lamps and LED modules/assemblies were generally too high for most consumer and commercial use. In recent years, prices have been falling and consequently, due to the aforementioned advantages, LED lighting is gaining widespread acceptance in both the consumer and commercial markets.
LEDs typically do not emit light in all directions, and require a plurality of LED elements to achieve sufficient luminosity. Therefore, light fixtures will in many cases have to be redesigned in order to perform optimally. Typically, such redesigns may incorporate the use of special lenses that compensate for the more directional light emitted from LEDs. Such light fixture redesigns may be more bulky and more costly to manufacture than traditional fixtures for fluorescent or incandescent light sources.
U.S. Pat. No. 4,748,543, for a HIDDEN SOURCE FLUORESCENT LIGHT WASH FIXTURE issued May 31, 1988, contains background information relevant to the present invention. The abovementioned patent and the various embodiments of the present invention, address offset hidden source type light fixtures designed especially for the purpose of providing architecturally distinctive indirect lighting treatments wherein a fixture (or row of side-by-side fixtures), flush mounted into a flat surface such as wall or ceiling of a room, “washes” a nearby flat surface such as a wall, floor or ceiling, perpendicular to the mounting surface, with uniform illumination.
In the abovementioned patent, a thin flexible offset reflective lining is adhesively attached to a rigid aluminum reflector mounting body extruded in a special compound curved shape having an offset lamp-surround portion blending into an extended “throw” portion so as to provide uniform “wash” illumination from the fluorescent lamp concealed within the lamp-surround portion.
U.S. Pat. No. 5,142,459, for a HIDDEN SOURCE FLUORESCENT LIGHT WASH FIXTURE issued Aug. 25, 1992, discloses further development of this type of light fixture with an alternative reflector configuration and associated mounting system for an improved “wash” light fixture of the offset hidden source type, based on refinements of the optical principles of U.S. Pat. No. 4,748,543, but providing new benefits with regard to illumination coverage, manufacturability, and reflector replaceability.
This product improvement allows configuration of a light fixture of the fluorescent offset-reflector hidden-light-source wall-wash type, such that it provides substantially uniform illumination along with improved shielding of direct light from the source and suppression of spurious highlights reflected from fixture surfaces.
Additionally, it provides a reflector mounting configuration in which a specially shaped curved reflector is secured to the fixture in a manner that enables the reflector to be easily installed, removed and replaced, and which also provides the unique curved reflector surface shape required in this type of fixture, uniformly and reliably.
However, despite the improvements obtained in the aforementioned patents, these types of light fixtures are designed for light sources that emit light in all directions, and are therefore not well suited for LED lights in general, and modern commercial LED assemblies in particular, which generally emit light from a side of a plane surface, only in the direction away from the side of the plane surface.
Additionally, while light fixtures according to embodiments disclosed in U.S. Pat. No. 5,142,459 provide significantly improved shielding from direct light, these types of light fixtures still allow unshielded view of the lighting elements from some viewing positions.
As such, considering the foregoing, it may be appreciated that there continues to be a need for novel and improved devices and methods for LED based light fixtures.